The new VP Roo Fueld makes combusion and mixing temperatures cooler. Good for 2 strokes! Must change jetting approx 6% richer. Best to increase compression too. Good for 4 strokes too.

Note: Race Fuel Above 100 – No point using it. Fuel testing will be done at Australian and FIM Wold Championships.

The benefits you can achieve by having components treated include:

• Increased wear resistance to rotating and friction bearing parts
• Increased time between rebuilds
• More consistent engine compression figures over time
• Better heat dissipation du eto increasing temperature coefficients
• An overall performance increase. HP, Torque and Revs.
• Reduced warping/cracking of susceptible components
• Should be done to Piston & Barrell as a minimum task

HGS Exhaust. VHM Cylinder Head. 185-190 main jet. Ignition timing 1.1mm BTDC.

The European exhausts are the best tested on the dyno and at the track.   The scalvini produced good power in the top end, and the engine needs to be tuned for this type of power, the pipe is thin and will get damaged easily , the damaged pipe will have a loss of power.  Van Hasselt exhaust is specially designed for MX, best mid range power and easy to race , and the construction is good.  the HGS has the best top end power out of all the pipes, but engine must be tuned to suit this for the rider.  All pipes have more power than the stock pipe. USA pipes, euro pipes included.  USA pipes crack alot. Euro pipes are stronger and make more power, but are not coated and rust easily.  Most of the power increase comes form the pipe, not the silencer .  The silencer does change the engine noise alot, but the dyno tests show no big power changes are made.

Some pistons on the compression side do not have a wear band-ring. You can order one from the rebound side and machine the piston to fit it so you have smoothness on compression (as it should be). Common SX65. Shivers have this as standard.

Note: Only use Mazzoochi Seals (a lot less drag).

Many different production types. Example: KTM Vertex is not the same piston as Vertex after-market type. Check weights! But both are quite good.  Some brand pistons are different heights, so your squish clearance can change.    VHM billet pistons do actually have a run in coating!     The 12 degree pistons change the port timing and also are flat , increasing the top end power .  Most manufacturers say to replace small size high rev pistons at 10 hours.  Most riders do them at 20-25 hours.     Using the dyno to test, most engines see more power made if a piston is replaced after  about 12 hours.   After about 12 hours some exhaust gas pass the compression rings, and enters the crankcases , this reduces the power of the engine a small ammount.   Using a new piston before an important race meeting is well worth while.  Modern hard coated cylinders with light alluminium pistons dont take long to run in at all.  Do not add more oil for run in.  Deglasing the cylinder when replacing the piston is worth doing, using only a soft scouring pad.  Adding a thin layer of oil or grease on your base gasket, will allow you to reuse it.  Cylinder head orings must be changed each year at least.   Always replace exhaust orings each piston change as well.  The KTM sx65 powervalve operates on exhaust pressure, its different, like the kart engines, so any change in the pressure-compression, changes the power curve of the engine. A new piston or even  Silencer repacking changes this too .  On the dyno, a new silencer fitted to a sx65 with reduce the power, for about 20 minutes!   Never fit a new silencer before a race to a sx65 !

This Italian company is spending more time and money making and testing Exhausts than others. Some of the 2 stroke systems add a lot of power. After installing a Scalvini on a SX85, the engine feels like it has had large modifications made. Expensive pipes. Some pipes are hard to fit (SX65). They can get damaged easy, and power losses result.  look great.

Development changes to expansion chamber and mufflers. Each exhaust is exactly the same from 1st stamping to the 50th stamping.

EHR products for making racing bikes go faster, but also the engines are easier to race as the power band becomes wider. The power doesn’t have a hard hit, so the kids like the set up. All the race parts have been tested on the dyno, then on bikes in Holland and we test them here. You can still make some mods yourself to improve the set ups too.

Treatment of gears for low friction and better shifting, done with a Tumbler/Vibration machine.

H.P.S.F Victoria Ph 03 9775 0898.